# US 10,482,808 B2 · Pixel control circuit and control method thereof, display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,482,808 B2 - Document ID: US10482808B2 - Status: Granted - Kind: B2 - Application number: 15/995,629 - Filed: 2018-06-01 - Published: 2019-04-25 - Granted: 2019-11-19 - Earliest claimed: 2017-10-19 - Assignees: Boe Technology Group Co., Ltd.; Beijing Boe Display Technology Co., Ltd. - Applicants: Boe Technology Group Co., Ltd.; Beijing Boe Display Technology Co., Ltd. - Inventors: Weifan Yang; Na Li - Web page: https://patentgrep.com/patent/US10482808B2 ## CPC - G09G 3/22: using controlled light sources - G09G 3/36: using liquid crystals - G09G 2300/08: Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements - G09G 2310/0256: with the purpose of reversing the voltage across a light emitting or modulating element within a pixel - G09G 2310/0291: Details of output amplifiers or buffers arranged for use in a driving circuit - G09G 2320/0238: Improving the black level - G09G 2320/0276: for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract A pixel control circuit and a control method thereof, and a display device. The pixel control circuit includes a control-signal output sub-circuit and a switch sub-circuit. An input terminal of the switch sub-circuit is electrically coupled to an output terminal of the control-signal output sub-circuit. An input terminal of the control-signal output sub-circuit is electrically coupled to a data line. The control-signal output sub-circuit is configured to: compare a voltage received by the data line with a reference voltage; and if a value of the voltage is equal to a value of the reference voltage, output a first control signal, otherwise output a second control signal. The switch sub-circuit is configured to be turned off under control of the first control signal and turned on under control of the second control signal. The reference voltage is a corresponding gamma voltage when the display panel is in a dark state. ## Claims ### Claim 1 A pixel control circuit, comprising: a control-signal output sub-circuit and a switch sub-circuit; wherein: an input terminal of the switch sub-circuit is electrically coupled to an output terminal of the control-signal output sub-circuit; an input terminal of the control-signal output sub-circuit is electrically coupled to a data line, and the control-signal output sub-circuit is configured to: compare a voltage received by the data line with a reference voltage; and if a value of the voltage received by the data line is equal to a value of the reference voltage, output a first control signal, otherwise output a second control signal; the switch sub-circuit is configured to be turned off under control of the first control signal and to be turned on under control of the second control signal; and the reference voltage is a corresponding gamma voltage when the display panel is in a dark state. ### Claim 2 (depends on 1) The pixel control circuit according to claim 1, wherein the control-signal output sub-circuit includes a comparison sub-circuit, an output sub-circuit, a first control-signal input terminal and a second control-signal input terminal; the comparison sub-circuit is electrically coupled to the input terminal of the control-signal output sub-circuit, and is configured to: compare the voltage received by the data line with the reference voltage; and output the first signal to the output sub-circuit if the value of the voltage received by the data line is equal to the value of the reference voltage, otherwise output a second signal to the output sub-circuit; a first terminal of the output sub-circuit is electrically coupled to the comparison sub-circuit, a second terminal of the output sub-circuit is electrically coupled to an output terminal of the control-signal output sub-circuit, a third terminal of the output sub-circuit is electrically coupled to the first control-signal input terminal, and a fourth terminal of the output sub-circuit is electrically coupled to the second control-signal input terminal; and the output sub-circuit is configured to: control the first control-signal input terminal to input the first control signal when the first terminal of the output sub-circuit receives the first signal, and output the first control signal by the second terminal of the output sub-circuit; and control the second control-signal input terminal to input the second control signal when the first terminal of the output sub-circuit receives the second signal, and output the second control signal by the second terminal of the output sub-circuit. ### Claim 3 (depends on 2) The pixel control circuit according to claim 2, wherein the comparison sub-circuit includes a first comparator and a second comparator, and the reference voltage includes a first reference sub-voltage and a second reference sub-voltage; the first comparator is configured to compare a positive voltage received by the data line with the first reference sub-voltage; the second comparator is configured to compare a negative voltage received by the data line with the second reference sub-voltage; the first reference sub-voltage is a corresponding gamma voltage having a positive polarity when the display panel is in the dark state; and the second reference sub-voltage is a corresponding gamma voltage having a negative polarity when the display panel is in the dark state. ### Claim 4 (depends on 2) The pixel control circuit according to claim 2, wherein the output sub-circuit includes a first output unit and a second output unit; a first terminal of the first output unit is electrically coupled to the comparison sub-circuit, a second terminal of the first output unit is electrically coupled to the first control-signal input terminal, and a third terminal of the first output unit is electrically coupled to the output terminal of the control-signal output sub-circuit; and a first terminal of the second output unit is electrically coupled to the comparison sub-circuit, a second terminal of the second output unit is electrically coupled to the second control-signal input terminal, and a third terminal of the second output unit is electrically coupled to the output terminal of the control-signal output sub-circuit. ### Claim 5 (depends on 4) The pixel control circuit according to claim 4, wherein the first output unit and the second output unit are different types of transistors. ### Claim 6 (depends on 5) The pixel control circuit according to claim 5, wherein the first output unit is an N-type transistor, and the second output unit is a P-type transistor. ### Claim 7 (depends on 5) The pixel control circuit according to claim 5, wherein the first output unit is a P-type transistor, and the second output unit is an N-type transistor. ### Claim 8 (depends on 1) The pixel control circuit according to claim 1, wherein the switch sub-circuit includes a first switch unit and a second switch unit; a first terminal of the first switch unit is electrically coupled to an input terminal of the switch sub-circuit, and a second terminal of the first switch unit is electrically coupled to a gate line of the display panel; and a first terminal of the second switch unit is electrically coupled to a third terminal of the first switch unit, a second terminal of the second switch unit is electrically coupled to the data line, and a third terminal of the second switch unit is electrically coupled to a pixel electrode of the display panel. ### Claim 9 (depends on 8) The pixel control circuit according to claim 8, wherein the first switch unit and the second switch unit are N-type transistors. ### Claim 10 (depends on 8) The pixel control circuit as claimed in claim 8, wherein the first switch unit is a P-type transistor, and the second switch unit is an N-type transistor. ### Claim 11 (depends on 8) The pixel control circuit according to claim 8, wherein the first switch unit is configured to be turned off under control of the first control signal, and to be turned on under control of the second control signal. ### Claim 12 (depends on 1) The pixel control circuit according to claim 1, wherein the first control signal is a high level signal and the second control signal is a low level signal. ### Claim 13 (depends on 1) The pixel control circuit according to claim 1, wherein the first control signal is a low level signal and the second control signal is a high level signal. ### Claim 14 (depends on 1) A display device, comprising a display panel, wherein the display panel includes a plurality of sub-pixel units, a plurality of data lines, and a plurality of pixel control circuits each of which is according to claim 1; and an output terminal of each of the pixel control circuits is electrically coupled to a pixel electrode of one of the sub-pixel units. ### Claim 15 (depends on 1) A control method of the pixel control circuit according to claim 1, comprising: comparing a voltage received from a data line with a reference voltage, outputting a first control signal if a value of the voltage received from the data line is equal to a value of the reference voltage, otherwise outputting a second control signal; switching off a connection between the data line and a pixel electrode under control of the first control signal; and switching on the connection between the data line and the pixel electrode under control of the second control signal; wherein the reference voltage is a corresponding gamma voltage when the display panel is in a dark state. ### Claim 16 (depends on 15) The control method according to claim 15, wherein comparing the voltage received from the data line with the reference voltage, outputting the first control signal if the value of the voltage received from the data line is equal to the value of the reference voltage, otherwise outputting the second control signal, includes: when the voltage received from the data line is a positive voltage, comparing the positive voltage with a first reference sub-voltage by using a first comparator, wherein the first reference sub-voltage is a corresponding gamma voltage having a positive polarity when the display panel is in the dark state; outputting the first control signal when a value of the positive voltage is equal to a value of the first reference sub-voltage; and outputting the second control signal when the value of the positive voltage is greater than the value of the first reference sub-voltage, wherein the reference voltage includes the first reference sub-voltage. ### Claim 17 (depends on 16) The control method according to claim 16, further comprising: when the voltage received from the data line is a negative voltage, comparing the negative voltage with a second reference sub-voltage by using a second comparator, wherein the second reference sub-voltage is a corresponding gamma voltage having a negative polarity when the display panel is in the dark state; outputting the first control signal when a value of the negative voltage is equal to a value of the second reference sub-voltage; and outputting the second control signal when the value of the negative voltage is less than the value of the second reference sub-voltage, wherein the reference voltage includes the first reference sub-voltage. ### Claim 18 (depends on 17) The control method according to claim 17, wherein when a polarity inversion control signal is a high level signal, the voltage received from the data line is the positive voltage, and the first comparator is used for comparison; and when the polarity inversion control signal is a low level signal, the voltage received from the data line is the negative voltage, and the second comparator is used for comparison. ### Claim 19 (depends on 16) The control method according to claim 16, wherein the first control signal is a high level signal and the second control signal is a low level signal. ### Claim 20 (depends on 16) The control method according to claim 16, wherein the first control signal is a low level signal and the second control signal is a high level signal.